Different eras of political history are frequently identified with royal dynasties, or great wars and revolutions.
Eras in the history of art and architecture may be distinguished by styles such as Renaissance, Gothic, Impressionist or Surrealist, and so on.
Techniques too have marked different eras over the centuries: from the primitive tools of the Stone Age, to the Industrial Age marked by steam and electrical power and the discovery of turbines, and engines.
Today, we have entered a new era: the computer age – an age which owes everything to inventors.
Charles Babbage, an English mathematician, is considered to be the great-grandfather of the computer. Over 150 years ago, in 1840 to be exact, he invented a sophisticated calculating machine, and called it the "Analytical Engine." As with many inventions, his creation was far in advance of its time.
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